Peroxisomes are cell organelles that are present in almost all eukaryotic cells and involved in a large range of metabolic pathways. The organelles are highly dynamic in nature: their number and enzyme content is highly variable and continuously adapts to prevailing environmental conditions. This review summarizes recent relevant developments in research on processes that are involved in the regulation of peroxisome abundance and maintenance. These processes include fission of the organelles, formation of new peroxisomes from the endoplasmic reticulum, autophagic degradation and segregation/inheritance during cell division.